Wind turbine device

ABSTRACT

A hybrid blade wind turbine device formed of at least a pair of straight outer airfoil blades, and a pair of inner helical wing blades, as supported for rotation within a safety protective cage structure, which wind turbine can be mounted in the vertical, horizontal, or other aligned operational positions. The inner helical half wing blades, being preferably somewhat shorter than the length of the outer airfoil blades, act to “regularize” the swirling wind regime flowing through the hybrid wind turbine, so as to maximize the efficiency of the outer airfoil blades. The helical half wing blades can be formed of individual segmented vane segments to provide improved operational capabilities for the overall hybrid wind turbine. To best harness annualized available wind conditions, the hybrid wind turbine can be customized, through modification of the number of vane segments, the selection of the specific shape of the outer airfoil blades, and the specific operational positioning of the outer airfoil blades. Alternatively, the helical half wing blades can be formed as generally smooth-walled blades.

I. RELATED PATENT APPLICATION

This patent application is a divisional of prior U.S. patentapplication, Ser. No. 10/629,370, filed Jul. 29, 2003, still pending.

II. FIELD OF THE INVENTION

This invention relates to wind turbine devices, and more particularly toa universal-axis wind turbine device having a combination of multipleblade designs and a surrounding safety cage structure.

III. BACKGROUND OF THE INVENTION

Various known designs of wind turbine structures include the commonpropeller blade type turbine, the so-called Darrieus blade type turbine,and the so-called Savonius blade type turbine.

Several Savonius or “S”-rotor blade designs are known, including thosetypified in Canadian Patent No. 1,236,030, EPO Publication No. 0040193B1, French No. 961,999, German No. 187865, Japanese Publication No.60-090992, Swedish No. 65,940, WIPO No. WO/99/04164, and U.S. Pat. Nos.1,697,574 and 4,293,274. Each of those various Savonius-type bladedesigns have inherent limitations, including the limitation of noiseduring operation, excessive vibration during operation, a tendency to“run away” during elevated wind speed operations and often excessivedrag created during rotation of the leeward or non-wind-gatheringportion of the blade's movement.

Further, various Darrieus-type turbine blade designs are disclosed inU.S. Pat. Nos. 1,835,018, 2,020,900, 4,112,311, 4,204,805 and 4,334,823.However, these Darrieus-type designs also have inherent deficiencies,including that only the middle one-third of their blade length (at leastfor curved Darrieus blade versions) efficiently creates power; that thefarther the distance from a curved blade to its axis of rotation, thegreater the likelihood, especially in large scale power generationunits, of a Darrieus type unit going into harmonic vibration andself-destructing; that all such Darrieus-blade type units are notself-starting, but need assistance in starting; and that in many windconditions they can, on a periodic basis, use up more energy than theyactually produce. Without proper controls and/or mechanical brakingsystems, Darrieus type units (like Savonius units) have been known to“run away” during elevated wind speed conditions.

Further yet, there have been attempts at combining a bucket-shapedSavonius-type drag blade system with a Darrieus-type curved lift bladesystem, as found in U.S. Pat. No. 3,918,839, and in Tanzawa, et al.,“Dynamic Characteristics of the self-controlled Darrieus-Savonius HybridWind Turbine System,” Proceedings of the CSPE-JSME-ASME InternationalConference on Power Engineering, Vol. 1, (1995), pp. 115-121(“Tanzawa”). Yet in U.S. Pat. No. 3,918,839, significant difficultiesarose relative to the operational, i. e., rotational, stability of theunit at high wind speeds. In Tanzawa, the addition of a Savonius bucketrotor to start the Darrieus rotor resulted in a reduction in the totalturbine power and high braking torque at higher rotational rates. Therewere also the above-noted inherent problems present in all separateDarrieus and Savonius-type blade systems.

Most available wind turbine designs have problems of excessive noise andvibration, often self-destruct in high wind conditions, some requireseparate start-up, braking or stopping mechanisms, and many are notconsidered safe, readily insurable or building -code permitted, at leastnot for use in congested urban settings.

Thus, there has been an ongoing need for a wind turbine design that canbe successfully incorporated into various building and tower structures,that produces minimal noise and vibration during operation, is capableof starting up and operating in each of low speed, steady, gusty, andhigh speed wind conditions, has a built-in self-regulation via aninherent structural geometry against over-speeding runaway conditions,is formed of blade designs that operate in essentially all windconditions and produce moderate drag during full rotational operation,which is easy to manufacture and ship, and which can be housed in a safeoperating package for use in crowded urban settings.

IV. SUMMARY OF THE INVENTION

The present invention comprises in one form a hybrid wind turbine formedof both an inner helical screw-type blade design, with the individualhelical blades formed of flexible segmented vane members operable as anair valve to allow air to pass between them when in their leeward(non-wind-gathering) position relative to the wind so as to reduce bladedrag, and at least a pair of outer generally straight airfoil blades,which are of greater overall length than the inner helical blades. Theentire hybrid blade combination is mounted for rotation within aprotective cage structure to prevent unwanted entry of humans, birds andother objects in the blade path, and to help with secure, low vibrationmounting, safety and insurability for urban settings.

The inner segmented helical screw-type S blades permit early start up ofthe hybrid turbine at low wind speeds. They also act as wind brakes atunduly high wind speeds to prevent runaway conditions. The outer airfoilblades enable the hybrid wind turbine to achieve high rotational speedsand resultant high energy production efficiencies at upper wind speeds.Together the helical and airfoil blades help maximize harvesting of windenergy. The present hybrid wind turbine operates with minimal noise andvibration, particularly since the segmented helical vane members operateat a rotational (varying torque) rate that does not exceed the speed ofthe wind by more than three and a half times and with a varying profilethat always presents generally the same overall blade area to the wind.(This is in distinct contrast to standard “non-twisted” “S” rotorswhich, in essence, offer a alternating high- or wide- and then a low- ornarrow-profile to the wind as they rotate.) This acts to substantiallyeliminate the “banging” noise and harmful action, especially in thesupport bearings, as found in many non-helical, non-twisted prior artSavonius-type turbine blades. The segmented helical screw blades, formedinto two helical half wing blades, can be selectively formed withdifferent numbers, and hence widths, of elongated vane segments, andwith different spacing between such vane segments, depending upon theoperational height at which the hybrid wind turbine will be mounted, andalso upon the average annual wind speed available at that operationalheight. Additionally, both the cross-sectional shape of the outerairfoils, and their operational distance from the inner helical blades,can be altered for the same reasons. The inner helical blades can bealternatively formed as generally smooth-walled blades, i. e., formedvia an edge-abutting or slightly overlapping series of flat panelsegments but that in either case do not have edge separation duringrotational operation.

The present hybrid wind turbine is of universal axis such that it can bemounted horizontally, vertically, or at any other near vertical orangular operational orientation as desired, and as specific mountingsurface conditions may require. It can be used in urban settings, suchas a single generation point with minimal transmission loss, such as fora so-called “zero energy” building. The overall shape of the presenthybrid wind turbine can be cylindrical, conical, frustro-conical, orother shape. Further, a belt-drive or direct-drive type permanent magnetalternator, a belt-drive or direct-drive type generator, oralternatively, a belt-drive or direct-drive type air motor can be usedto harness and convert the wind-generated power from the hybrid windturbine.

V. BRIEF DESCRIPTION OF THE DRAWINGS

The means by which the foregoing and other aspects of the presentinvention are accomplished and the manner of their accomplishment willbe readily understood from the following specification upon reference tothe accompanying drawings, in which:

FIG. 1 is a front elevation view of the hybrid wind turbine of thepresent invention, showing certain blade and some protective cagecomponents;

FIG. 2 is a top plan view of the hybrid turbine of FIG. 1;

FIG. 3 is similar to FIG. 1, but showing the various turbine blades ashaving been rotated 45 degrees from their position in FIG. 1;

FIG. 4 is a left end view of the hybrid turbine of FIG. 2;

FIG. 5 is a perspective view of the hybrid blade configuration of thehybrid turbine of FIG. 1;

FIG. 6, 7, and 8 are similar to FIGS. 1, 2 and 4, respectively, showingfor the turbine blade components, but with cage structure removed forbetter viewing;

FIG. 9 is a perspective view of the hybrid turbine of FIG. 1, as mountedhorizontally, with partial cage, frame mounting, and power generationstructure;

FIG. 10 is similar to the hybrid turbine of FIG. 9, but with segmentedinner helical blades, less certain cage components, and as mounted in avertical orientation;

FIG. 10A is similar to the hybrid turbine of FIG. 10, as mounted in avertical orientation, and showing an air motor and air storage tank;

FIG. 11 is a graph representing performance characteristics (comparingwind speed versus blade tip speed) for both the present invention andknown prior wind turbine designs;

FIG. 12 is an enlarged cross-section of the present invention's airfoilblade, as taken along the lines 12-12 in FIG. 7;

FIG. 13 is a cross-sectional view, similar to FIG. 12, but of a modifiedairfoil blade design for different wind applications;

FIGS. 14 a, 14 b, and 14 c are similar to FIGS. 6, 7 and 8, but show onetype of helical vane segmentation structure for certain operationalapplications;

FIGS. 15 a, 15 b, and 15 c are additional enlarged cross-sectionalviews, similar to

FIGS. 14 a, 14 b, and 14 c, but of a different inner helical bladeconfiguration showing modified vane segmentation structure for differentoperational applications;

FIG. 16 a is an enlarged end view of a segmented turbine blade assembly,similar to

FIG. 15 c, but partially rotated, to better depict certain segmentedvane blades and separation aspects;

FIG. 16 b is a further enlarged end view of one helical half wing,showing vane segments and support structure;

FIG. 17 depicts, as an exploded assembly view, how the individual curvedflat panels attach to a helical half wing frame to form one of themodified smooth-walled inner helical blade assemblies; and

FIG. 18 is a perspective view of the hybrid turbine of FIG. 9, asmounted in a modular combination with a second hybrid turbine, andshowing a shared battery storage unit.

VI. DETAILED DESCRIPTION OF THE INVENTION

Having reference to the drawings, wherein like reference numeralsindicate corresponding elements, there is shown in FIGS. 1 through 5 anillustration of a hybrid wind turbine device forming one embodiment ofthe present invention, namely a non-segmented blade version, asgenerally denoted by reference numeral 20. Hybrid turbine 20 includes anouter protective safety frame or cage generally denoted by referencenumber 22, and a combination turbine blade assembly 23 comprising a pairof non-segmented (generally smooth-walled) helically twisted innerturbine blades, namely helical half wing blades 24 a, 24 b, and a pairof diametrically opposed outer airfoil blades 26 a, 26 b. Each of thehelically twisted inner turbine blades and the outer airfoil bladescooperates in wind conditions to drive the operation of the other typeblade. Further, each of the helically twisted inner turbine blades andthe outer airfoil blades cooperates to form an inherent structuralgeometry which guards against over-speeding run away conditions.

The cage 22 comprises a pair of generally concave hub ends 28 a, 28 b,each comprising a rigid outer support ring member 30. There is also asimilar central cage support ring member 32. Each of hub ends 28 a, 28 bhas a central journal hub 34 and outwardly-extending support arms 36connected to ring 30. The helically twisted inner turbine blades may bejournaled for rotation about a common axis and having an outer diameter31 (FIG. 4). For example, in one embodiment, a main turbine mast 38,with reduced shaft ends 40, may be rotatably journaled within eachjournal hub 34. Preferably, each journal hub 34 carries suitableself-lubricating ball bearing bushings (not shown) to help reducerotational friction, vibration, and noise. A suitable alternator, suchas, for example, a direct drive permanent magnet alternator, seereference numeral 35 in FIG. 9 and 10, as attached to a shaft end 40,can be used to collect and convert the “rotational energy” powerharnessed by the present wind turbine 20.

Safety cage 22 also comprises a series of elongated tie members 42, allof which are rigidly affixed, such as by threaded fasteners or welding,to the respective end and central support ring members 30, 32. Althoughomitted from FIGS. 1-5 for better viewing, the outer cylindrical surfaceof safety cage 22 is preferably covered with a suitable protective wiremesh 45, such as formed of commercially available rectangular-mesh wirefencing material (see FIGS. 9 and 10). It will be appreciated that theprotective mesh 45 may be made of any suitable material, including forexample, a plastic, or other durable material. It will be furtherappreciated that if the protective mesh 45 is constructed of asufficiently strong material, the safety cage 22 may be significantlyreduced, if not eliminated completely, as long as the turbine mast 38 issupported and journaled for rotation by the protective mesh. Theprotective mesh 45 allows the swirling wind regimes present aboutturbine 20 to reach both sets of the inner helical blades 24 a, 24 b,and outer airfoil blades 26 a, 26 b, yet otherwise prevent unwantedentry of human limbs, birds in flight, or other large objects that mightotherwise undesirably impinge upon the respective turning blades. Ifdesired and where considered necessary, and particularly for use on acongested urban rooftop, high-rise, and other building-attachedapplications, an even finer mesh screen can be used for the protectivemesh 45; it can be formed with sufficiently small enough gage screenwire to prevent children's hands, broomsticks, metal rods, and othersmaller objects from being inserted through the wire mesh. On the otherhand, in some special applications, an open (e.g., 2 inch by 2 inch)heavy wire mesh (not shown) can be used alone to structurally supportthe axial cage structure for the present hybrid wind turbine's uses.

Preferably, the elongated airfoil blades 26 a, 26 b are formed asstraight length blades, of a symmetrical cross section, with ends 25that extend beyond the length of the inner helical blades 24 a, 24 b.Further, the overall length of the airfoil blades 26 a, 26 b ispreferably with the range of some 105% to 150% greater than the overalllength of the helical blades 24 a, 24 b, and more preferably, some 120%greater. This allows a substantial percentage of the available windenergy, especially at higher wind speeds, to be harnessed by the moreefficient airfoil blades 26 a, 26 b. Advantageously, the somewhatshorter length of the helical blades (vs. larger airfoil blades) allowsfor use of concave-shaped hub ends 28 a, 28 b, which in turn allows roomto house an associated energy transformation, power conversion and/orpower generation unit, namely, for example a direct drive permanentmagnet alternator 35 which may be attached directly to an electricalcircuit (not shown), may be attached to a battery 37 for electricalstorage, or the like. It will be appreciated by one of ordinary skill inthe art that any suitable generator may be used as the alternator 35,including, for example, a belt-drive or direct-drive type permanentmagnet alternator, a belt-drive or direct-drive type generator, oralternatively, a belt-drive or direct-drive type air motor.

As best seen in FIGS. 5, 6, 8, and 17 (the latter an exploded assemblyview), a series of transverse blade support struts extend radially fromturbine mast 38, and rotate therewith, to appropriately support, at eachend as well as in the central area, the two helical half wing blades 24a, 24 b, as well as the outer airfoil blades 26 a, 26 b. Morespecifically, these supports include pairs of end support struts 46, 48,and central support struts 50. As shown in FIG. 6, traverse bladesupport struts may radially extend from the central axis withoutextending from the turbine mast 38, thereby allowing the turbine mast 38to not necessarily continuously extend through the two helical half wingblades 24 a, 24 b. In other words, the turbine mast 38 may beconstructed of a pair of non-contiguous mast sections which cooperate tosupport the helical half wing blades 24 a, 24 b. If needed, evenadditional auxiliary support struts can be used, as seen in FIGS. 9, 10,and 17 with intermediate support struts 52, giving a total of fivesupport struts for each helical half wing 24 a, 24 b. The latter ispreferred when, as seen in FIG. 17, particularly for ease of manufactureand shipping in a small container in a flat condition, eachsmooth-walled helical half wing blade 24 a, 24 b is formed of fourdistinct flexible panels 84 a, 84 b, 84 c, and 84 d, and then assembledin abutting or overlapping edge fashion (via fastening with pop rivetsor other connector—not shown—to the respective struts on mast 38) tocreate the respective generally smooth-walled helical half wing blades.It will be further appreciated that the intermediate supports struts 52may be detached from the turbine mast 38 allowing the mast and supportsto be disassembled for shipment and reassembled at a distant location.

FIG. 9 depicts a horizontal mounting for the hybrid wind turbine 20 ofthe present invention, where the hybrid wind turbine 20 has itsprotective cage 22 mounted upon a low-lying support stand 51. As seen, adirect drive permanent magnet alternator 35 can be used, as mountedwithin the concave hub end 28 b. The horizontal mounting arrangement ofhybrid wind turbine 20 shown in FIG. 9 is suitable for roof-top mountingapplications, such as in urban buildings, or mounted at ground level.

There is shown in FIG. 10, however, a more preferred vertical-mountedorientation for hybrid wind turbine 20. As shown there and as laterdescribed, the helical half wings are depicted as being formed ofmultiple vane segments. The support stand 53 is modified from that ofstand 51 of the horizontal mounting depicted in FIG. 9, but is otherwisethe same. As typically used in low power electrical situations, a lowRPM direct drive permanent magnet alternator 35 is again used. However,a chain drive-type or belt drive-type generator (not shown) could bealternatively utilized. The vertical mounting arrangement shown in FIG.10 is preferred because, regardless of which direction the wind isblowing from, such a vertically-aligned turbine 20 is able to harnesswind from essentially all the swirling, gusty wind regimes beingpresented against it.

As shown in FIG. 10A, there is illustrated an embodiment of the hybridturbine 20 wherein a direct-drive type air motor 39 is used as anassociated energy transformation, power conversion and/or powergeneration unit. The air motor 39 may be, for example, an air motormarketed by Gast Manufacturing, Inc., of Benton Harbor, Mich. The airmotor 39, which converts rotational energy into pressurized air,operates to pressurize an air storage tank 41. The pressurized air inthe tank 41 may then be utilized by an air motor driven generator 43 toproduce an electric current (i.e., an air-to electric generator) asdesired, and whether continuously, on-demand, or during peak energydemand periods.

Turning to FIG. 12, there is shown the cross-sectional shape of theairfoil blades 26 a, 26 b. As seen, generally symmetrical airfoil bladeshapes are used, although non-symmetrical airfoil blade shapes may alsobe used. They can be formed of extruded or molded aluminum, molded orextruded plastic, or similar materials. More specifically, and asparticularly chosen for use in lower height applications, wheregenerally lower wind speed conditions will normally occur, or otherwisein urban buildings under 50 stories (i.e., generally under 500 feet orapproximately 152.5 meters in height), a low-speed design of airfoilblade is selected. That is, for such lower widespread operationalsettings the preferred airfoil blade shape, per FIG. 12, is selected asa low-speed National Advisory Committee for Aeronautics (“NACA”), NACA0015 airfoil-type design blade. As seen, such a NACA 0015 airfoil bladedesign has generally a wide thickness T and a squat parabolic length Lof the blade in cross-section. In one prototype made in accordance withthis invention, the airfoil blades 26 a, 26 b were formed of extrudedaluminum, where T was approximately 0.9004 inch, and L was approximately6 (six) inches.

On the other hand, there is seen in FIG. 13 a modified cross-sectionalshape of the outer airfoil blades, 26 a′, 26 b′, namely for use in acombination turbine blade assembly 23 in high wind speed applications,or otherwise for use in higher urban building elevations (generally from500 feet or 152.5 meters high and above). In those potentially moreextreme wind applications, a different and higher speed airfoil bladedesign is preferred, namely a high-speed NACA 0012 airfoil blade design.As seen in FIG. 13, and as contrasted to the airfoil blade profile ofFIG. 12, such a modified airfoil design for generally higher windspeeds, generally has a long length L, and thin thickness T. In adifferent prototype made in accordance with this invention, again formedof extruded aluminum, T was chosen as 0.7202 inch and L was chosen as 6(six) inches. It will be appreciated by one of ordinary skill in the artthat any suitable material may be used to construct the airfoil blades26 a, 26 b, including, for example, extruded aluminum, a aluminum sheetcladding over foam plastic, molded or extruded plastic material such asPVC, polystyrene or polycarbonate, a combination of the above, or othersimilar material.

As seen when comparing FIGS. 12 and 13, the shape of the outer airfoilblades can be adjusted as needed depending on the given wind powergeneration requirements. Even other shapes of airfoil blades, includingnon-symmetrical blade designs, can be utilized, depending on the annualwind conditions expected for a given installation. That is, for extremewind conditions, and for very high elevations (e.g., over 50 stories andgenerally over 500 feet or approximately 152.5 meters in height), theairfoil blades 26 a, 26 b can be greatly modified as needed. In thatway, the combination turbine blade assembly 23 can be customized withinthe dimensional confines of a given hybrid wind turbine 20, yet withoutrequiring changes to the turbine's other component parts.

As shown in FIGS. 1-8 (and as will be further described relative toFIGS. 14 a- 14 c, and 15 a-15 c), the respective inner helical halfwings 24 a, 24 b have preferably been twisted through 180 degrees, i.e.,from one end to the other. However, that helical blade twist can fallwithin the range of end-to-end twist from as little as approximately 45degrees to as much as approximately 270 degrees, while still achievingthe operational efficiencies of the hybrid wind turbine 20 of thepresent invention. Further, the smooth-surfaced inner helical half wingblades 24 a, 24 b can each be formed of one continuous wing member, ormore preferably, for ease of manufacture and shipping purposes and asexplained above, be formed of four or more individual flat-curved panelsegments whose edges abut or slightly overlap one another, and aremounted to the respective support struts via rivet fasteners, or otherconnector, i.e., to form each overall smooth-surfaced helical half wing.

Turning to FIGS. 14 a, 14 b, and 14 c, there is shown another and thepreferred form of the invention, namely one having a segmented-typehybrid turbine blade assembly, generally denoted by reference number 54.Segmented turbine blade assembly 54 utilizes the same end struts 46, 48,central strut 50, turbine mast 38 with reduced ends 40, and same outerairfoil blades 26 a, 26 b. However, instead of utilizing the generallysmooth-surfaced helical inner turbine blades 24 a, 24 b (of combinationblade assembly 23 per FIG. 6), the modified type blade assembly 54utilizes elongated segmented-type helical inner turbine blades 56 a, 56b. More specifically, as seen in FIGS. 14 a, 14 b, and 14 c, each suchhelical half wings 56 a, and 56 b is respectively formed of, forexample, six separate vane segments, denoted by reference numerals 58 a,58 b, 58 c, 58 d, 58 e, and 58 f. Thus, such a separate six (6)-vanesegment design (for each helical half wing 56 a, 56 b) results in atotal of twelve (12) vane segments. That type segmented helical bladedesign would preferably be used in higher heights, and greater windspeed installations, such as when used in a hybrid wind turbine 20mounted atop a high rise building, whether mounted horizontally orvertically. Of course, it will be understood that the number of vanesegments may vary according to design considerations and may do so fromas little as two vane segments (for lower speed wind installations) toas many as may be manufactured and fastened to the turbine bladeassembly.

On the other hand, such as for use in lower height and lower speed windinstallations, there is shown in FIGS. 15 a, 15 b, and 15 c a modifiedform of segmented type combination turbine blade assembly, generallydenoted by reference numeral 60. Again, modified segmented turbine bladeassembly 60 utilizes the same support struts 46, 48, and 50, centralmast 38 with reduced ends 40, and straight airfoil blades 26 a, 26 b.However, this time each segmented helical half wing 62 a, 62 b isrespectively formed of only three vane segments 64 a, 64 b, 64 c, for atotal of six (6) such vane segments across modified blade assembly 60.

The attachment of the respective vane segments to a tubular supportframe 70 will now be described. The support frame may be formed oftubular metal, plastic, or similar material. As depicted in FIGS. 16 aand 16 b, relative to modified assembly 60, each respective vane segment64 a, 64 b, and 64 c has a first longitudinal or fixed edge 66 that isaffixed via a fastener 68 (such as a pop rivet) to the support frame 70.There is also a second longitudinal or free edge 72 which is freefloating, i.e., not affixed to any structure, and, which overlaps, by anoverlap distance OD, the affixed edge 66 of the next adjacent vanesegment. It has been found that the overlap distance OD can be in therange of from approximately zero to 2 inches. Thus, one vane segmentoverlaps and cascades over the next adjacent outer vane segment. Forexample, as seen in FIG. 16 a, the free longitudinal edge 72 of vanesegment 64 b is free floating and separated by a separation distance SDfrom the first or fixed longitudinal edge 66 of adjacent vane segment 64c. It will be appreciated that in another embodiment, the free edge 72may substantially abut, rather than overlap the affixed edge 66 of thenext adjacent vane segment. It will be further appreciated that in yetanother embodiment, the free edge 72 may be separated from the affixededge 66 of the next adjacent vane segment forming a permanent air slotwith the separation distance SD. Frame 70 is preferable formed oftubular galvanized steel material. Each vane segment is preferableformed of an ultraviolet light-inhibiting plastic, such as ultravioletlight-resistive polycarbonate material or ultraviolet light-resistivepolyvinyl chloride (PVC) material, fiber glass sheeting, aluminum, lightsteel sheeting, Kevlar, polyurethane, rubber sheeting material, or thelike.

During rotation of the hybrid wind turbine formed with a segmented bladeassembly, the separation distance SD can vary greatly depending on thematerial used for each respective vane segment, the running width W ofeach vane segment, the flexibility present in a given vane segmentbetween its fixed longitudinal edge 66 and its free edge 72, and thegiven wind speeds (i.e., air pressure) being encountered by the windturbine at any given moment.

For example, prototype units were made in accordance with the presentinvention, where the overall blade length for airfoil blades 26 a, 26 bwas approximately 9.5 feet, the overall length of the helical half wings62 a, 62 b was approximately 8 feet, the diameter of joined helical halfwings (designated as D_(H) in FIG. 16 a), was approximately 50 inches,the respective vane segments 64 a, 64 b, and 64 c were formed of aflexible material, with a vane width W of approximately 9 inches, a vanethickness of some 0.2 inches, and there was an approximately 2 inch gappresent between the outer edge of the helical half wings and theinnermost edge of the respective airfoil blades. In the presence of a 15mph wind, it was found that the separation distance SD, and henceelongated air slot, created between the vane segments was in the rangeof approximately ⅛ to ¾ inch, and generally about ⅜ inch. Moreover, itwas also found that, in winds generally above 25 mph, and where the vanesegments were formed of a substantially flexible material, such asrubber sheeting, and regardless if a given portion of a helical halfwing was in a wind-gathering or non-wing gathering condition, therespective free floating edge 72 was maintained at a substantiallyconstant separation distance SD. In effect, the presence of vanesegmentation allowed the helical half wings to have air slots thatcooperatively act as an “air valve”, i.e., between respective vanesegments. On the other hand, when the vane segments were formed of asomewhat stiffer, yet flexible, sheeting material such as ultravioletlight-resistive polycarbonate, it was found that for the same prototypeunit, the separation distance SD created was somewhat greater for theoutermost vane segments, e.g. vane segments 58 a and 58 b in FIG. 14 c,and somewhat lesser for the inner vane segments, e.g., segments 58 cthrough 58 f.

It will be appreciated by one of ordinary skill in the art that eventhough specific examples of measurements are giving in illustratedembodiment above, various modifications in the dimensions of thecomponents may be made without deviating from the teachings of thepresent invention. For example, the diameter of the outer airfoil blades26 a, 26 b may be in the range of approximately 4 to 24 inches greaterthan that of the outermost edge of the inner half wing blades 24 a, 24b, the length of the turbine mast 38 may be in the range ofapproximately 8 to 10 feet, the length of each half wing blade 24 a, 24b may be in the range of approximately 6 to 9 feet, and the length ofeach airfoil blade 26 a, 26 b may be in the range of approximately 9.5to 11.5 feet. Similarly, the half wing blades 24 a, 24 b may have athickness in the range of approximately 0.03 to 0.25 inches, each vanesegment 58 a, 58 b, 58 c, 58 d, 58 e, 58 f may have a width in the rangeof approximately 3 to 11 inches, the diameter of the half wing blades 24a, 24 b may be in the range of approximately 24 to 50 inches, and thecross sectional thickness of each airfoil blade 24 a, 24 b may be in therange of approximately 0.5 to 1.5 inches.

Thus, the segmentation-type combination turbine blade assemblies 54 and60 have distinct advantages over the smooth surface-type blade assembly23 (where the helical half wings are formed of only a generally smoothsurface, or of edge-abutting flat panel sections creating a generallysmooth surface, and without any segmentations and without otherwisehaving separate flexible vane segments with free-floating edges). Forexample, the elongated segmentation of the helical half wings in thepresent invention, which is the preferred embodiment, results in asubstantial reduction in the air drag, contrary to what was previouslypresent with Savonius type blade systems, including the twisted S-typehelical versions thereof. By way of explanation, as the rear or leewardside of a non-segmented Savonius blade rotates into position against thewind, i.e., after just being in a wind gathering mode, it enters anon-gathering wind position. In that condition, the blade's concave backside presents a substantial drag against performance.

However, with the present invention's preferred segmentation structure,oncoming swirling wind is allowed to simply filter through air slotspresent in the back side of the cascading, overlapping, and segmentedhelical vane segments (e.g., vane segments 64 a, 64 b, 64 c). Thisoccurs due to the presence of the air slots provided via segmentationdistances SD. (To visualize, this is not unlike the slots formed amongand between the edges of a series of Venetian blinds as helicallytwisted 180° from end-to-end.) This allows one vane segment to create avacuum effect to lift the free edge of the next adjacent vane. Forexample, it has been noted that at start up and at lower speedrotations, the respective vanes of the helically twisted blades of thepresent hybrid wind turbine 20, formed as having vane segments, tend toclose on one another as they take in air, and then slightly open on thebackside or leeward side of a cycle, i.e., the non-wind gathering side,to create elongated air slots and thereby reduce air drag by letting airthrough. However, as described above, when at full rotational speeds andparticularly with very flexible vane material (e.g., rubber sheeting),the separation distances SD created between vane segments essentiallystay constant throughout the full rotational cycle, i.e., during boththe wind gathering and non-wind gathering cycle portions. In effect, thepresence of the vane segments in the helical half wings helpssubstantially overcome the prior art problem of so-called “blade profiledifferentiation”, as was common with most Savonius blade systems. Thus,the segmented vane structure helps substantially increase theperformance capability for the respective helical half wing portions ofthe segmented combination blade assemblies 54,60, particularly in highspeed winds, e.g., over 45 mph.

Then, during high operational, i.e., higher wind speed, conditions, thevane segments, even when in their wind-gathering condition, have thetendency to “open up”. This allows yet even more wind to flow throughthe air slots formed by the segmentation distances SD. This, in turn,results in allowing the segmented helical half wings to rotate evenfaster than they normally would, because they are under the rotationalinfluence of the much higher operational speed airfoil blades 26 a, 26b. Thus, the normally slower inner Savonius-type turbine blades have thetendency to get out of their own way, i.e., to increase overall hybridturbine performance and efficiencies at higher wind speeds.

Then, further still, in extremely high rotational speed conditions, thevane segments actually act as an “airbrake”, relative to the airfoilblades, helping to prevent runaway conditions when operational safetymight otherwise be of concern for the turbine 20. That is, under extremewind conditions, the segmented helical half wings, even though the vanesegments thereof are opened up with air slots, tend to continuouslybrake or slow down the otherwise excessively freely-rotating outerairfoil blades 26 a, 26 b, to keep the entire hybrid blade assembly 23from over-speeding.

It has been found that in normal operation, the more segmented (i.e.,more individual vane segments) the helical half wings are, the lessefficient they are. This is because with such a segmented hybridturbine, it takes more wind at start up to commence turbine rotation.However, once reaching higher operational speeds, the presence of theextra number of vane segments helps the inner helical turbine blades to,in effect, get out of their own way, thereby helping minimize their owndrag effect on the more efficient outer airfoil blades. Thus, it will beappreciated that the choice of individual vane segmentation will dependon the projected operating conditions of the hybrid turbine. Forexample, in places with traditionally lower wind speeds, a smallernumber, for example two vane segments with one air slot per helical halfwing, segments may be utilized, while at locations with traditionallyhigher wind speeds, a greater number of segments may be utilized.

Further yet, it has been noted in smoke-type testing that the segmentedhelical vanes tend to, in effect, “standardize” the turbulent air withinany given gusty wind regime blowing through them, which has the resultof greatly assisting the outer airfoil blades' performance. That is, asbelieved and understood, the segmented twisted vanes tend to organize(or perhaps better stated as “regularize”) the wind currents before theyreach the respective outer straight airfoil blades. This has the effectof yet further increasing the efficiency of the hybrid wind turbine 20,as especially noted along the outer ends thereof, i.e., by maximizingthe efficiency of the outer airfoil blades via standardizing the amountand flow pattern of wind currents that reach them.

Still further, it has been found via testing that by using straightlength blades, rather than curved length blades, for airfoils 26 a, 26b, when in combination with the inner helical blades 56 a, 56 b (or 62a, 62 b), the overall efficiency and operational speed of the presenthybrid wind turbine, in any given speed wind, is greatly improved. As tothe form of attachment for the respective outer straight airfoil blades26 a, 26 b, those blades, as preferably formed of a suitable extrudedaluminum material, are welded via welds 75 into the end of therespective metal support struts 46, 48, 50 (see, for example, FIG. 16 a)which are part of support frame 70. Depending upon given wind speeds,the operational diameter for the respective airfoil blades 26 a, 26 bcan be chosen to be as little as say 36 inches and as much as 74 inches,with the diameter of the helical half wing blades then proportionallyvaried. Such a selected change in the radial positioning for therespective outer straight airfoil blades is quite advantageous. This isbecause the positioning of the outer airfoil blades 26 a, 26 b, can becustomized for a given installation, all depending upon the expectedavailable wind conditions and regimes. For example, when winds arenormally of generally higher speeds, the airfoil blades are formed tohave a smaller operating diameter. But when installed where windconditions are normally of only modest speeds, the airfoil blades 26 a,26 b can be positioned at a more outermost position. This approachrecognizes that, while airfoil blades in the outermost positions cansupply more angular momentum to the hybrid wind turbine, they can alsotend to increase chances for unwanted vibration for the overall hybridwind turbine.

Preferably, the smooth surface helical half wings 24 a, 24 b ofcombination blade assembly 23 (per FIGS. 1-8) are formed, whether as onepiece or several abutting flat panel sections, of a material that willreadily withstand the outdoor elements, e.g., rain and snow, and highand low temperatures, such as an ultraviolet light-inhibitedpolycarbonate material, or a similar UV-light inhibited PVC (polyvinylchloride) material, or any other suitable flexible material that cantake the shape of frame 70 and be formed into the helical blades 24 a,24 b. Further, the elongated vane segments, such as vanes 58 a through58 f, or 64 a through 64 c, can be formed of the same type of material.In any event, such vane segments should be formed of a relativelyflexible material, so that the separation distance SD created betweenvanes can be maximized during normal rotation.

As seen in FIG. 16 b, the fixed edge 66 of each respective vane segmentis captured and held within an aerodynamically-shaped vane nose bracket82. The various nose brackets 82 with attached vanes then can berespectively fastened along their length to the support frame 70, by wayof a series of fasteners 68, such as pop rivets. This aerodynamicallyshaped nose bracket 82 may help reduce air drag at the leading fixededge 66 of the respective vane segment.

Seen in FIG. 11 is a graphical chart of the respective performanceefficiencies, over various wind speeds, of different types of windturbine designs as listed, including the hybrid wind turbine design ofthe present invention. More specifically, FIG. 11 depicts graphicallythe relationship of turbine efficiency percentage in the form of theratio of blade tip speed to wind speed, for numerous different types ofprior wind turbine blade designs (see dotted lines). That is, as seen inFIG. 11, the hybrid wind rotor turbine of the present invention (seesolid line), which is self starting, is very efficient over a largerrange of blade tip to wind speed ratios. Then, as shown in solid line,the efficiency performance of the hybrid wind turbine of the presentinvention reflects that the initial performance at lower wind speedsperforms at the expected output efficiency of normal Savonius-typeturbine units. However, at higher wind speeds, the present hybrid unit'sperformance becomes closer to what is found with traditionalDarrieus-type straight-blade turbine units.

Further, FIG. 11 depicts that the hybrid wind turbine of the presentinvention runs no faster than approximately 3½ wing tip speed versuswind speed, and thus, minimizes any chance of runaway conditions. Thatis, FIG. 11 shows graphically that as wind speeds move higher, thepresent hybrid turbine advantageously is progressively constrained bythe typical air drag effects common to helical Savonius-type turbineunits, thus resulting in the controlled performance unique to thepresent hybrid wind turbine design.

In operation, the helical half wing blades of the present hybrid turbineblade invention (whether of smooth-walled or vane segment type) commencerotation quickly, i.e., with as little as 4 to 6 mph wind. Thus, theinner helical half wing blades 24 a, 24 b quickly start the overallhybrid wind turbine 20 into rotation. Thereafter, the straight airfoilblades 26 a, 26 b begin rotating, again as initially powered by thehelical blades, and then at higher wind speeds they start harnessingwind and generating power at their much higher efficiency level, i.e. attheir higher blade-tip-velocity-to-wind velocity ratio.

Through testing it has been found that there is an optimum ratio of thewidth W_(T)(see FIG. 6) of the combination hybrid blade assembly 23 (oralternatively, of the modified segmented combination turbine bladeassemblies 54, 60) of the present invention, versus the length L_(T) ofthose blade assemblies. That is, for generally higher speed winds, thatso-called turbine aspect ratio, including the “reach” or “pitch”relative to the overall swept area, optimally and preferably isapproximately a ratio of 1:3. On the other hand, for generally lowerspeed winds, the optimal turbine aspect ratio is instead lower andapproximately 3:5. Furthermore, it will be appreciated that the airfoilblades 26 a, 26 b may be radially positionally adjustable relative tothe half wing blades 24 a, 24 b to thereby help maximize wind harvestingdepending upon the local wind conditions and the mounting height of theturbine blade assembly 23. Still further, it will be appreciated thatthe number and position of airfoil blades may be varied, including, forexample, having three or more airfoil blades. Thus, as seen, the presenthybrid turbine can be readily customized for a given wind-harvestingapplication.

Turning to FIG. 18, there is depicted pair of horizontally mountedhybrid wind turbines 20-1 and 20-2, of the present invention, whereinthe hybrid wind turbines 20-1 and 20-2 are mounted in a modularconfiguration. As seen, each hybrid wind turbine 20-1, 20-2 may bemounted in a separate support stand 51-1, 51-2, and the support stands51-1, 51-2 may be then assembled in abutting or overlapping edge fashion(via fastening with bolts or other connector—not shown—to the respectiveouter support ring member 30-1, 30-2) to create the combined hybrid windturbine. Each hybrid wind turbine 20-1,20-2 may further have its ownrespective direct-drive permanent magnet alternator 35-1, 35-2, or othersuitable energy transformation unit, connected to an energy storage unit(battery) 37-1, 37-2. If desired, the two storage units 37-1, 37-2 maybe electrically combined to enhance their storage capacity.

It will be appreciated that the two hybrid wind turbines 20-1 and 20-2may be combined in a number of different ways, and in a number ofdifferent configurations. While it is preferable that the turbine mastof each hybrid wind turbine 20-1 and 20-2 be mounted so as to operateseparately and independently, it will be understood that the two mastsmay be joined so as to form a combined, elongated central mast.Similarly, the various components associated with the hybrid windturbines 20-1 and 20-2, may be combined or separated as desired,including having a single alternator, a single battery, or the like.

From the foregoing, it is believed that those skilled in the art willreadily appreciate the unique features and advantages of the presentinvention over previous types and designs of wind turbines and bladestherefore. Further, it is to be understood that while the presentinvention has been described in relation to particular preferred andalternate embodiments as set forth in the accompanying drawings and asabove-described, the same nevertheless is susceptible to change,variation and substitution of equivalents without the pressure from thespirit and scope of this invention. It is therefore intended that thepresent invention be unrestricted by the foregoing description anddrawings, except as may appear in the following appended claims.

74. A method of achieving maximized wind harvesting for generatingelectrical power, comprising the steps of: providing a rotatablysupported helically twisted blade with a plurality of flexible elongatedvane segments, wherein each vane segment has a fixed edge and a freeedge, and the free edge of one segment one of at least partiallyoverlaps and substantially abuts the fixed edge of the next adjacentvane segment; and creating separation air slots between the elongatedvane segments by allowing the free edge of at least one vane segment torise up from the fixed edge of the next adjacent vane segment duringrotation of the rotatably supported helically twisted blade, wherein,when operating at high rotational speeds, the respective separation airslots created between vane segments of the helically twisted bladeoperate as an air brake to help prevent runaway rotational conditions.75. The method of claim 74, wherein the free edge of each vane segmentoverlaps the fixed edge of the next adjacent vane segment by a distancein the range from approximately 0 to 2 inches.
 76. The method of claim74, wherein during rotational operation, the free edge of each vanesegment is adapted to rise up from the fixed edge of the next adjacentvane segment by a separation distance in the range of betweenapproximately 1/8″ to 3/4″.
 77. The method of claim 74, wherein duringrotational operation, the separation distance between theradially-outermost mounted vane segments is greater than the separationdistance between the radially-innermost mounted vane segments.
 78. Themethod of claim 74, further comprising the step of mounting each of thevane segments within an aerodynamically-shaped vane nose bracket. 79.The method of claim 74, further comprising the step of mounting thehelically twisted blade to a substantially vertically aligned rotatableturbine mast.
 80. The method of claim 74, wherein the helically twistedblade is rotatably supported within a protective safety cage.
 81. Themethod of claim 74, further comprising the step of converting rotationalenergy of the rotatably supported helically twisted blade intoelectrical energy.
 82. The method of claim 74, further comprising thestep of converting rotational energy of the rotatably supportedhelically twisted blade into electrical energy utilizing one of a directdrive permanent magnet alternator, a belt drive permanent magnetalternator, a direct drive generator, a belt drive generator, a directdrive air motor and a belt drive air motor.
 83. The method of claim 74,wherein the helically twisted blade is twisted from one end to the otherend, through a twist rotation of one of approximately 45°, 90°, 180°,and 270°.
 84. The method of claim 74, further comprising the step ofmounting a plurality of substantially straight airfoil blades fixed forrotation with the helically twisted blade and rotatably supportedtherewith.
 85. The method of claim 84, wherein the airfoil blades arelonger than the helically twisted blade.
 86. The method of claim 84,wherein the helically twisted blade and airfoil blades are rotatablysupported within a protective safety cage.
 87. The method of claim 84,further comprising the step of converting rotational energy of therotatably supported helically twisted blade and airfoil blades intoelectrical energy.
 88. The method of claim 87, wherein the convertingstep comprises utilizing one of a direct drive permanent magnetalternator, a belt drive permanent magnet alternator, a direct drivegenerator, a belt drive generator, a direct drive air motor and a beltdrive air motor.
 89. The method of claim 84, wherein the helicallytwisted blade is twisted from one end to the other end, through a twistrotation of one of approximately 45°, 90°, 180°, and 270°.
 90. A methodof overcoming blade profile differentiation in a helical wind turbineblade having a windward side and a leeward side, comprising the stepsof: forming a rotatably supported helically twisted blade to comprise aplurality of flexible elongated vane segments, wherein each vane segmenthas a fixed edge and a free edge, and the free edge of one segment atleast one of partially overlaps and substantially abuts the fixed edgeof the next adjacent vane segment; and raising the free edge of at leastone vane segment up from the fixed edge of the next adjacent vanesegment during rotation of the rotatably supported helically twistedblade, thereby providing an air valve opening to reduce air drag whenthe leeward side surfaces of the helically twisted blade are beingperiodically presented against the wind.
 91. The method of claim 90,wherein during rotation, the free edge of each vane segment is adaptedto rise up from the fixed edge of the next adjacent vane segment by avariable separation distance in the range of between approximately ⅛″ to¾″.
 92. The method of claim 91, wherein during rotational operation, thevariable separation distance between the radially-outermost mounted vanesegments is greater than the variable separation distance between theradially-innermost mounted vane segments.
 93. The method of claim 90,further comprising the step of mounting the helically twisted blade to asubstantially vertically aligned rotatable turbine mast.
 94. The methodof claim 90, further comprising the step of converting rotational energyof the rotatably supported helically twisted blade into electricalenergy.
 95. The method of claim 94, further comprising the step ofconverting rotational energy of the rotatably supported helicallytwisted blade into electrical energy utilizing one of a direct drivepermanent magnet alternator, a belt drive permanent magnet alternator, adirect drive generator, a belt drive generator, a direct drive air motorand a belt drive air motor.
 96. The method of claim 90, wherein thehelically twisted blade is twisted from one end to the other end,through a twist rotation of one of approximately 45°, 90°, 180°, and270°.
 97. The method of claim 90, further comprising the step ofmounting a plurality of substantially straight airfoil blades fixed forrotation with the helically twisted blade and rotatably supportedtherewith.
 98. The method of claim 97, wherein the airfoil blades arelonger than the helically twisted blade.
 99. The method of claim 97,further comprising the step of converting rotational energy of therotatably supported helically twisted blade and airfoil blades intoelectrical energy.
 100. The method of claim 97, wherein the convertingstep comprises utilizing one of a direct drive permanent magnetalternator, a belt drive permanent magnet alternator, a direct drivegenerator, a belt drive generator, a direct drive air motor and a beltdrive air motor.
 101. The method of claim 97, wherein the helicallytwisted blade is twisted from one end to the other end, through a twistrotation of one of approximately 45°, 90°, 180°, and 270°.
 102. Themethod of claim 90, further comprising the steps of lowering the freeedges of the respective vane segments towards the respective fixed edgesof adjacent vane segments when the leeward side is in position of takingin air, and raising the free edges up from adjacent fixed edges ofadjacent vane segments as an air valve when the windward side is inposition of being forced against wind, thereby creating reduced air dragby letting air flow from the leeward side through the separation airslots as formed between the respective raised free edges and fixed edgesof the vane segments.
 103. A wind turbine apparatus for harvesting windenergy, comprising: a helical blade journaled for rotation; the helicalblade being separated into a plurality of lengthwise blade segments,each blade segment having a radially inward fixed edge, and a radiallyoutward free edge, the respective free edges being adapted, during windturbine operation, to rise up through a separation distance away fromthe respective fixed edges, the free edges thereby moving from a normalrest position to a full operating position.
 104. The apparatus of claim102, further comprising a turbine mast journaled for rotation andwherein the helical blade is carried by the turbine mast;
 105. Theapparatus of claim 102, wherein the free edge of a given blade segmentradially overlaps the fixed edge of the next adjacent blade segment.106. The apparatus of claim 102, and an aerodynamically shaped noseelement mounted on the fixed edge of the respective blade segments so asto help reduce air drag.
 107. The apparatus of claim 102, and at least apair of airfoil blades fixed with and located radially outward of thehelical blade.
 108. The apparatus of claim 107, wherein the overalllength of the airfoil blades is in the range of approximately 105% to150% of the overall length of the helical blade.
 109. The apparatus ofclaim 107, wherein two airfoil blades are carried by the turbine mast atdiametrically opposed positions.
 110. The apparatus of claim 107,wherein a plurality of airfoil blades are carried by the turbine mast atcircumferentially symmetrical positions.
 111. The apparatus of claim107, wherein the airfoil blades are substantially straight.
 112. Theapparatus of claim 107, wherein the airfoil blades are radiallypositionally adjustable relative to the helical blade, to thereby helpmaximize wind harvesting depending upon the local wind conditions andthe mounting height of the wind turbine apparatus.
 113. The apparatus ofclaim 107, and a protective cage enclosing the helical blade and airfoilblades.
 114. The apparatus of claim 102, wherein the helical blade ismounted in one of substantially horizontal, vertical, and angularalignment.
 123. A method of maximizing wind energy harvesting by a windturbine while minimizing air drag and over-speed conditions, comprisingthe steps of: mounting a helically twisted blade supported for rotation;mounting a plurality of substantially straight airfoil blades forrotation, wherein the substantially straight airfoil blades are mountedradially outwardly of the helically twisted blade and rotate with thehelically twisted blade; wherein the helically twisted blade is adaptedto operate in low wind speed conditions to start the rotation of theairfoil blades, wherein the airfoil blades and the helically twistedblade cooperate in mid-range wind speed conditions to rotate both theairfoil blades and the helically twisted blade, and wherein thehelically twisted blade is adapted to operate in high speed conditionsto produce an air drag to prevent the over-speed rotation of the airfoilblades and the helically twisted blade.
 124. The method of claim 123,wherein the helically twisted blade comprises a plurality of flexibleelongated vane segments, wherein each vane segment has a fixed edge anda free edge, and wherein in low speed conditions the free edge of atleast one vane segment at least one of partially overlaps andsubstantially abuts the fixed edge of the next adjacent vane segment, tothereby assist in starting the rotation of the airfoil blades.
 125. Themethod of claim 124, wherein in mid-range wind speed conditions the freeedge of at least one vane segment variably raises away from the fixededge of the next adjacent vane segment thereby providing an air valveopening to reduce air drag when the leeward side surfaces of thehelically twisted blade are being periodically presented against thewind.
 126. The method of claim 124, wherein in high speed conditions thefree edge of at least one vane segment raises away from the fixed edgeof the next adjacent vane segment thereby providing air drag to helpprevent the over-speed rotation of the airfoil blades.
 127. The methodof claim 124, wherein during rotation, the free edge of each vanesegment is adapted to rise up from the fixed edge of the next adjacentvane segment by a variable separation distance in the range of betweenapproximately ⅛″ to ¾″.
 128. The method of claim 124, wherein duringrotational operation, the variable separation distance between theradially-outermost mounted vane segments is greater than the variableseparation distance between the radially-innermost mounted vanesegments.
 129. The method of claim 123, further comprising the step ofconverting rotational energy of the rotatably supported helicallytwisted blade and airfoil blade into electrical energy.
 130. The methodof claim 129, further comprising the step of converting rotationalenergy of the rotatably supported helically twisted blade intoelectrical energy utilizing one of a direct drive permanent magnetalternator, a belt drive permanent magnet alternator, a direct drivegenerator, a belt drive generator, a direct drive air motor and a beltdrive air motor.
 131. The method of claim 123, wherein the helicallytwisted blade is twisted from one end to the other end, through a twistrotation of one of approximately 45°, 90°, 180°, and 270°.